A Direction Restricting Device for the Inner and Outer Tubes of a Bicycle Seat Post

ABSTRACT

The present invention provides a direction restricting device for the inner and outer tubes of a bicycle seat post, comprising at least one axial groove arranged on the wall of one of the tubes, and a direction restricting element fastened to the other tube at the position relative to the axial groove wall; said direction restricting element may be inserted into the axial groove and at least includes an elastic slider provided with an axial opening in the middle; the direction restricting element may be inserted into the axial groove so as to enable the axial outer walls of the direction restricting element to attach to the axial inner walls of the axial groove to eliminate the interspace between the slider and the axial groove to prevent from deflection and wobbling and to reinforce the steadiness of both tubes when the inner and outer tubes rotate relative to each other.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a direction restricting device for theinner and outer tubes of a bicycle seat post, and more specifically, toa structure that may eliminate the rotary interspace between the innertube and the outer tube of a bicycle seat post so as to prevent fromdeflection and wobble when said inner and outer tubes rotate relative toeach other.

2. Description of the Prior Art

The seat post is used for supporting the seat, and normally, the seatpost of a bicycle includes at least an outer tube and an inner tubejoined to each other so as to adjust the seat height. In order toprevent the outer tube and the inner tube from rotating, generally, adirection restricting device is arranged between the inner and outertubes to limit the inner tube to axial movements, such as the directionrestricting arrangement of bicycle suspension system disclosed in U.S.Pat. No. 006,145,862. According to FIG. 3B shown in U.S. Pat. No.006,145,862, a plurality of sets of opposing flats are arranged betweenthe outer tube 14 and the inner tube 13, and needle bearings 36-39 aredisposed between the opposing flats so as to allow the inner tube 13 tofreely slide within the outer tube 14. However, the height of the needlebearings 36-39 may become varied after operating for a long time, thatis, the needle bearings 36-39 may not stay in the same horizontalposition relative to the height, because the contacted friction planesand the friction resistances between the outer tube 14 and the innertube 13 are different, and therefore, the measurement or height that theinner tube 13 moves axially within the outer tube 14 will be affected.In order to ameliorate the aforementioned drawback, the seat post needsto be taken apart to adjust the needle bearings 36-39 to stay in thesame horizontal position relative to the height. In addition, aninterspace occurs between the axial walls of the aforesaid opposingflats between the outer tube 14 and the inner tube 13, and saidinterspace may cause deflection and wobbling of the tubes when the innerand outer tubes rotate.

It is against this background and the problems associated therewith thatthe present invention has been developed.

SUMMARY OF THE INVENTION

It is a primary object of the present invention to provide a directionrestricting device for the inner and outer tubes of a bicycle seat postthat may not only restrict the axial movement of the inner tube but alsoeliminate the rotary interspace between the inner tube and the outertube of a bicycle seat post so as to prevent from deflection and wobbleof the inner and outer tubes when they rotate relative to each other.

The present invention is characterized in that the direction restrictingdevice includes at least one axial groove arranged on the wall of one ofthe inner and outer tubes, and a direction restricting element fastenedto the other tube at the position relative to the axial groove wall;said direction restricting element may be inserted into the axial grooveand at least includes an elastic slider provided with an axial openingin the middle; the direction restricting element may be inserted intothe axial groove so as to enable the axial outer walls of the directionrestricting element to attach to the axial inner walls of the axialgroove to eliminate the interspace between the slider and the axialgroove to prevent from deflection and wobbling and to reinforce thesteadiness of both tubes when the inner and outer tubes rotate relativeto each other.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a stereogram of the seat post in accordance with a firstembodiment of the present invention.

FIG. 2 is an exploded view of portion of a first embodiment of thepresent invention.

FIG. 3 is a cutaway view of a first embodiment of the present inventionin a complete assembled mode.

FIG. 4 is an enlarged view of portion of FIG. 3.

FIG. 5 is a cross-sectional view of 5-5 shown in FIG. 3.

FIG. 6 is a cutaway view of 6-6 shown in FIG. 5.

FIG. 7 is an exploded view of a second embodiment of the presentinvention.

FIG. 8 is a cutaway view of a second embodiment of the present inventionin a complete assembled mode.

FIG. 9 is an enlarged view of portion of FIG. 8.

FIG. 10 is a cross-sectional view of A-A shown in FIG. 8.

FIG. 11 is an exploded view of a third embodiment of the presentinvention.

FIG. 12 is a cutaway view of a third embodiment of the present inventionin a complete assembled mode.

FIG. 13 is an enlarged view of portion of FIG. 12.

FIG. 14 is a cross-sectional view of B-B shown in FIG. 12.

FIG. 15 is an exploded view of a fourth embodiment of the presentinvention.

FIG. 16 shows the appearance of the inner tube in accordance with afourth embodiment of the present invention.

FIG. 17 is a top view showing the cross-section of the inner and outertubes in a complete assembled mode in accordance with a fourthembodiment of the present invention.

FIG. 18 is an exploded view of a fifth embodiment of the presentinvention.

FIG. 19 shows the appearance of the inner tube in accordance with afifth embodiment of the present invention.

FIG. 20 is a top view showing the cross-section of the inner and outertubes in a complete assembled mode in accordance with a fifth embodimentof the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

The means for achieving the aforesaid objective and the functions of thepresent invention will become apparent from the following description,taken in connection with the accompanying drawings, wherein a preferredembodiment of the present invention is disclosed.

Referring to FIG. 1 to FIG. 6, a first embodiment of the presentinvention comprises: an outer tube 10 having an internal wall which isprovided with a plurality of axial grooves 11 spaced in equidistantarrangement, and two inner sides of said axial grooves 11 arerespectively disposed with an axial groove wall 12; an inner tube 20having an end inserted into said outer tube 10 and provided with anouter wall, at the position relative to each axial groove 11 of saidouter tube 10, screwed respectively with a direction restricting element21 by a screw piece 200; said direction restricting element 21 protrudesfrom the outer wall of said inner tube 20 and is allowed to be insertedinto the axial grooves 11 of said outer tube 10. Wherein, said directionrestricting element 21 includes a resilient unit 23 shaped in a longstrip and a slider 22 with elasticity and abrasion resistance. Thecenter of said slider 22 is provided with an axial opening 24 of whichthe radial diameter is less than the radial width of said resilient unit23 so as to allow the resilient unit 23 to insert into the axial opening24 and to be fastened. When said resilient unit 23 is inserted into theaxial opening 24 of the slider 22, the axial outer walls 25 of theslider 22 are pushed outwards by the tension of the resilient unit 23,as shown in FIG. 5 and FIG. 6.

Referring to FIG. 3 to FIG. 6, when the inner tube 20 is inserted intothe outer tube 10, the slider 22 of the direction restricting element 21arranged on the inner tube 20 is also inserted into the axial groove 11of the outer tube 10 and the axial outer walls 25 of the slider 22 arepushed outwards by the tension of the resilient unit 23 to attach to theaxial groove walls 12 so as to eliminate the interspace between theslider 22 and the axial groove 11, as shown in FIG. 5 and FIG. 6, andfurther to prevent from deflection and wobble when the inner tube 20 andthe outer tube 10 rotate relative to each other. Moreover, the directionrestricting element 21 is fastened to the inner tube 20, so that eachdirection restricting element 21 will keep fixed without breaking awayfrom the inner tube 20. Referring to FIG. 7 to FIG. 10, different fromthe first embodiment of the present invention, the resilient unit 23 ofthe direction restricting element 21 and the cross section of the axialopening 24 of the slider 22 disclosed in a second embodiment of thepresent invention are upside-down T-shape, as shown in FIG. 10, so as toprevent the upside-down T-shaped resilient unit 23 from sliding out ofthe axial opening 24 when engaging with each other. The axial outerwalls 25 of the slider 22 arranged within the direction restrictingelement 21 of the inner tube 20 are pushed outwards by the tension ofthe resilient unit 23 to attach to the axial groove walls 12 of theaxial groove 11 on the outer tube 10. In addition, the further functionof a second embodiment is described as the aforesaid in a firstembodiment of the present invention.

Referring to FIG. 11 to FIG. 14, different from the second embodiment ofthe present invention, the resilient unit 23 of the directionrestricting element 21 and the cross section of the axial opening 24 ofthe slider 22 disclosed in a third embodiment of the present inventionare T-shape, as shown in FIG. 14. The resilient unit 23 and the crosssection of the axial opening 24 of the slider 22 are T-shape. When thedirection restricting element 21 is inserted into the axial groove 11 ofthe outer tube 10, the axial outer walls 25 of the slider 22 arrangedwithin the direction restricting element 21 of the inner tube 20 arepushed outwards by the tension of the resilient unit 23 to attach to theaxial groove walls 12 of the axial groove 11 on the outer tube 10. Saidresilient unit 23 has a side 230 facing the axial groove 11 of the outertube 10; moreover, the side 230 is allowed to touch the wall of saidaxial groove 11 so as to reinforce the steadiness of both tubes when theinner tube 20 and the outer tube 10 rotate relative to each other, asshown in FIG. 14.

Referring to FIG. 15 to FIG. 17, different from the three aforesaidembodiments of the present invention, the direction restricting element21 disclosed in a fourth embodiment of the present invention is notarranged with a resilient unit; said direction restricting element 21disclosed in a fourth embodiment only includes a slider 22 withelasticity and abrasion resistance provided with an axial opening 24 inthe middle; the slider 22 is a little greater than the axial groove 11in width. When said slider 22 is inserted into said axial groove 11, theaxial outer walls 25 of said slider 22 may be squeezed so as to beinserted into the axial groove 11, so that the axial outer walls 25 ofsaid slider 22 and the axial groove walls 12 of the axial groove 11 maykeep attached to each other to eliminate the interspace between theslider 22 and the axial groove 11, as shown in FIG. 17, so as to preventfrom deflection and wobbling as well as to reinforce the steadiness ofboth tubes when the inner tube 20 and the outer tube 10 rotate relativeto each other.

Referring to FIG. 18 to FIG. 20, different from the fourth embodiment ofthe present invention, the axial opening 24 of the slider 22 arrangedwithin the direction restricting element 21 disclosed in a fifthembodiment of the present invention is allowed to receive a resilientunit 23 having a tooth face 231 that faces the longitudinal outer wallsof the axial opening 24, as shown in FIG. 18, so that the elasticityeffect of the resilient unit 23 is augmented. When the resilient unit 23is inserted into the axial opening 24 of the slider 22, the axial outerwalls 25 of the slider 22 are pushed outwards by the tension of theresilient unit 23 to attach to the axial groove walls 12 of the axialgroove 11 so as to eliminate the interspace between the slider 22 of thedirection restricting element 21 and the axial groove 11 of the innerand outer tubes to prevent from deflection and wobbling of the tubeswhen the inner tube 20 and the outer tube 10 rotate relative to eachother.

According to the aforementioned, as shown in the present invention, theaxial outer walls 25 of the slider 22 are allowed to attach to the axialgroove walls 12 of the axial groove 11 arranged on the outer tube 10 soas to eliminate the interspace between the slider 22 of the inner tube20 and the axial groove 11 of the outer tube 10 to prevent fromdeflection and wobbling when the inner tube 20 is inserted into theouter tube 10.

The direction restricting element 21 disclosed in the aforesaidembodiments of the present invention is configured on the outer wall ofthe inner tube 20; said direction restricting element 21 is also allowedto be arranged on the inner wall of the outer tube 10; the axial grooves11 are disposed to the outer wall of the inner tube 20 when thedirection restricting element 21 is arranged on the inner wall of theouter tube 10.

What we claimed is:
 1. A direction restricting device for the inner andouter tubes of a bicycle seat post, comprising: at least an outer tubeand an inner tube joined to each other, wherein the wall of one of theinner and outer tubes is provided with at least one axial groove, andthe other tube at the position relative to the axial groove wall isarranged with a direction restricting element allowed to be insertedinto the axial groove; wherein said direction restricting elementincludes a slider with elasticity and a resilient unit, wherein saidresilient unit is allowed to be inserted into an axial opening arrangedin the middle of said slider, and the radial diameter of the axialopening of said slider is less than the radial width of the resilientunit, so that the axial outer walls of said slider may be pushedoutwards by the tension of said resilient unit to cause said directionrestricting element to be inserted into said axial groove, and thus, theaxial outer walls of the slider arranged within said directionrestricting element may also be pushed towards to attach to the axialinner walls of said axial groove.
 2. The direction restricting devicefor the inner and outer tubes of a bicycle seat post as claimed in claim1, wherein said direction restricting element is fastened to the outerwall of the inner tube, and said axial groove is arranged on the innerwall of the outer tube.
 3. The direction restricting device for theinner and outer tubes of a bicycle seat post as claimed in claim 1,wherein said resilient unit and the cross section of said axial openingare T-shape.4. The bicycle seat post structure as claimed in claim 2,wherein the outer side of said upper valve and the outer side of saidlower valve respectively kiss the relative surfaces arranged to thehollow valve, and both engage with each other by inclines.
 4. Thedirection restricting device for the inner and outer tubes of a bicycleseat post as claimed in claim 2, wherein said resilient unit and thecross section of said axial opening are T-shape.
 5. The directionrestricting device for the inner and outer tubes of a bicycle seat postas claimed in claim 1, wherein said resilient unit and the cross sectionof said axial opening are upside-down T-shape.
 6. The directionrestricting device for the inner and outer tubes of a bicycle seat postas claimed in claim 2, wherein said resilient unit and the cross sectionof said axial opening are upside-down T-shape.
 7. A directionrestricting device for the inner and outer tubes of a bicycle seat post,comprising: at least an outer tube and an inner tube joined to eachother, wherein the wall of one of the inner and outer tubes is providedwith at least one axial groove, and the other tube at the positionrelative to the axial groove wall is arranged with a slider withelasticity and abrasion resistance; wherein said slider, provided withan axial opening in the middle thereof and a little greater than theaxial groove in width, is allowed to be inserted into the axial groove;wherein said slider inserted into said axial groove may cause the axialouter walls of the slider to attach to the axial inner walls of saidaxial groove.
 8. The direction restricting device for the inner andouter tubes of a bicycle seat post as claimed in claim 7, wherein theaxial opening of said direction restricting element is allowed toreceive a resilient unit.
 9. The direction restricting device for theinner and outer tubes of a bicycle seat post as claimed in claim 8,wherein said resilient unit has a tooth face that faces the longitudinalouter walls of the axial opening.
 10. The direction restricting devicefor the inner and outer tubes of a bicycle seat post as claimed in claim9, wherein said slider is fastened to the outer wall of the inner tube,and said axial groove is arranged on the inner wall of the outer tube.